I just bought a set of Denise yesterday and I absolutely hate them... and the store won't take them back except for credit. I know that's better than nothing but... wah!
I have the Boye set and I really prefer the metal needles but of course it has some drawbacks. Their sizes are not all consistant with other brands - ie Boye size 6 is 4.25mm whereas others are 4.00mm. The set also lacks a short enough cable to make a 16" circular.
I prefer the Boye by leaps and bounds to the Denise but I see an Options in my future... maybe once I buy enough yarn and other goodies to soak up the Denise purchasing blunder.